Several varieties of input devices exist for performing operations in portable electronic devices. Some examples of input devices include buttons, switches, keyboards, mice, trackballs, touch pads, joy sticks, touch screens and the like. Some examples of portable electronic devices include media players, remote controls, personal digital assistants (PDAs), cellular phones, etc.
A user can cause an operation to be performed in a portable electronic device by applying an input to an input device. In one example, a user can move a cursor displayed on a display screen of the portable electronic device by touching an input device in a particular motion. In another example, a user can select an item displayed on the display screen by pressing an input device in a particular location.
Input devices that provide touch sensitive surfaces, such as touch panels and touch screens for example, are becoming increasingly popular because of their ease and versatility of operation. With touch sensitive surfaces, various sensor elements can be provided relative to a surface of an electronic device, and an input can be detected by sensing a change in some measure, such as capacitance for example, that is associated with the sensor elements and that exceeds a particular threshold level.
If the threshold level is set too low, the touch sensitive surface can become too sensitive, allowing unintended actions (e.g., setting the touch sensitive surface on a table) or effects (e.g., noise) to be detected as an input. If the threshold level is set too high, the touch sensitive surface can become too insensitive, allowing intended input actions (e.g., a light touching of the surface) to go undetected.
Accordingly, determining a proper threshold level for a touch sensitive device can provide unique challenges.